The present invention relates to an airbag device for protecting an occupant in a movable subject, such as a vehicle, in case of emergency, such as a collision of the vehicle.
An airbag device installed in a vehicle, for example, an automobile, includes a folded airbag, a housing member for accommodating the airbag, and an inflator (gas generator) for inflating the airbag by spouting or ejecting a gas in the event of the collision.
In most of the airbag devices for a driver's seat, the housing member is formed of a retainer and a module cover which can be opened or torn. The airbag and the inflator are attached to the retainer, and the airbag is covered by the module cover. When the inflator is actuated, the module cover is opened or torn, so that the airbag is inflated toward an interior of the vehicle.
In most of the airbag devices for a front passenger's seat, the folded airbag is accommodated in a container in the form of a receptacle, and the container is covered by a lid. When the inflator is actuated, the lid is opened, or starts opening like a door, so that the airbag is inflated in the interior of the vehicle.
As one kind of the conventional airbag devices, there is an airbag device wherein a tether belt is disposed inside the airbag. One or front end of the tether belt is sewn to a distal end portion of the airbag, and a rear end thereof is connected to the retainer or container. In case the inflator is actuated, the airbag is inflated until the tether belt is stretched tightly.
In the conventional airbag device, however, in case the inflator is being actuated to inflate the airbag, a protruding length of the airbag from the retainer or the container can not be adjusted.
Accordingly, an object of the present invention is to provide an airbag device, wherein an airbag user can be protected based on a condition of a vehicle and/or user.
Another object of the invention is to provide an airbag device, wherein a protruding length of the airbag from an airbag holding device can be adjusted based on a vehicle speed and user's weight.
A further object of the invention is to provide an airbag device as stated above, wherein the holding condition of the airbag is selected at an optimum value to protect the user.
Further objects and advantages of the invention will be apparent from the following description of the invention.